CETACEANS
Under the Environment Protection and Biodiversity Conservation Act 1999, all cetaceans are protected in Australian waters. Interference or capture of free-ranging cetaceans without a permit for any purpose other than rescue or euthanasia (see Chapter 46) of stranded animals is illegal.
Under scientific licence, issued by the relevant state or territory, research may be conducted on free-ranging cetaceans, which may involve capture and physical or chemical restraint. Gales et al. (2009) provide guidelines for the treatment of marine mammals in field research.13.1 Capture and physical restraint
The need to capture and restrain free-swimming, free- ranging cetaceans is rare and primarily involves entrapped, entangled or debilitated or abandoned calves. Free-ranging cetaceans can be caught in nets. Seine nets can be used to encircle the animal and then the area gradually reduced inside the perimeter until the animal can be physically restrained. Hoop nets can also be used to catch small cetaceans that bow ride boats (D Blyde pers. comm.). The incidence of entanglement of free-ranging cetaceans is increasing (see Chapter 46). Disentanglement is specialised, requiring the expertise and skill of highly trained operators. The handling and restraint of free-swimming or stranded cetaceans is specialised and potentially dangerous and should only be carried out by appropriately trained and licenced personnel. There is potential for injury to both the animal and people. Small odontocete (toothed) cetaceans can bite and their teeth are sharp. They are strong and can weigh over 300 kg. Care must be taken when working around the tail of any cetacean as significant injury may result if struck by it. Trauma to the animal from thrashing may result if not appropriately restrained.
Handling and restraining cetaceans in managed care is frequently required to facilitate moving animals between facilities or conducting routine husbandry or veterinary procedures (examination, venipuncture, other sampling, endoscopy, radiography, sonography, assisted or forcefeeding, other minor procedures). Many of these can be performed using operant conditioning, making them safer and less stressful for the animals and personnel.
A training program to facilitate transportation and handling should be incorporated into the husbandry program of all cetaceans in managed care (Blyde and Vogelnest 2008; Dold and Ridgway 2014). Cetaceans in managed care can be herded into small, shallow areas where they are easier to catch. Nets, slings and stranding devices built into pools can be used to facilitate capture and handling. Most small cetaceans (tube too far and block the right bronchus (Dold and Ridgway 2014).Once the animal is intubated, anaesthesia is maintained with sevoflurane or isoflurane in oxygen. Anaesthesia should be monitored for oxygen saturation, pulse rate and
ETCO2 concentration. ETCO2 should be maintained below 40 mmHg by the rate and depth of ventilation. Electrocardiography and monitoring the minimum inhibitory concentration of volatile anaesthetic agent are recommended. Direct arterial blood pressure can be measured by cannulation of the median artery of the pectoral flipper using ultrasound-guided catheterisation (Ivancic et al. 2014). The median blood pressure in 10 general anaesthetic procedures in cetaceans was 44 mmHg, which improved to 75 mmHg with support that included increasing IV fluid rates, decreasing inhalational anaesthetic levels and dobu- tamine (0.2-2.0 μg∕kg per min) IV (Bailey 2016; D Blyde pers. comm.). Extubation and replacement of the ‘goosebeak’ remain a critical area for success of the procedure and re-intubation should be considered if the patient does not begin to breathe spontaneously.
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